Abstract

The sounding square array resistivity method had been used to estimate strike orientation in a sub
surface anomaly model. The advantage of square array are more sensitif in an anisotropic medium
such as strike than inline array. Strike is an important factor to placed an array configuration in
resistivity method. The array commonly lay down paralel or perpendicular with a strike depend on
anomaly structure. The mapping square array was used to detect the model anomaly.The sounding
square array were measured by rotating array with azimuth 0° , 45° ,90° ,135° and 180° . The
sounding square array had an electrode spacing 1 m, 1,4 m, 2 m and 2,8 m. Azimuthal apparent
resistivity was obtained by calculation and then was plotted into Rossete diagram. The estimation of
strike orientation was determined perpendicularly from maximum azimuthal apparent resistivity. The
mapping square array used 10 m array spacing with 1 m electrode spacing. The Wenner array used 5
m with 0,5 m electrode spacing.Strike orientation was estimated on N 90 E. This estimation was based
on result each electrode spacing on the sounding square array. The existing model anomaly were
detected on 5 m until 7 m on mapping square array. The result of Wenner array modeling showed that
anomaly model was detected on 2,5 m until 3,5 m on N 40 W. This result showed that the sounding
square array can be applied to determine strike orientation which usually exist on geological structure